Switch plug



Aug. 30, 1932. c, c. MAURER ET Al.

SWITCH PLUG Filed May 5, 1950 Patented Aug. 3o, i932l ramal unirse STATES PATENT FW'C CHARLES o. MAURERAND NORMAN D. VEA, or DOVER, OHIO,v AssieNoRs V'ro DOVER". MANUFACTURING COMPANY, lor DOVER, OHIO, A CORPORATION or OHIO swrron PLUG Appiicatio'n fiiea May 5, 1930.Y serial No. 449,555.

This invention relates to improvements in v 5f irons and other tools.`

' the switch itself and its contacts will be pro- The object of this invention is to provide a yform of plug more durable than those here- Atofore used under similar conditions.

Further objects are to provide a form of construction in which the vswitch operating piece will not become heated, in which the operating piece willbe ina position for inl 'binding'post for the socket terminal 20. The

stant and convenient manipulationrin which tected from excessive heat, in which the cord or cable can beso connected that thereV will be minimum interference with the manipulation of the tool or with the operation of the switch, and in which all of theseV objects can be accomplished with minimum expense and a switch produced which willr be of maximum durability and reliability. v

f In the drawing:

, to one end of the body portions 10 and y11` by4 a metal jacket 16 havingarms 17 received employing my invention.

Figure 2 is a view of the same with one side portion of the casing removed and the remaindershown in section to disclose the terminals, switch'members, etc. Y Y

- Figure 3 is'a'section drawn generally to line 3 3 of Figure 2.

Figure 4 is a detail view of the stationary contact terminal of the switch and associated Figure v1 is a side view of a switch plug parts Viewed at right angles to their posi-1 erence characters throughout the several views. Y Y

` The improvedplug has body members 1() and 11'ormecl of insulatingv material dividedy substantially in a plane commonto the axis of the cord receiving socketV 13 and the operating'` piece or lever 14. Theplug portion 15 is also of, insulating material and is held in recesses in the sides lof the body portions 10 and 11 whereby the three insulatingmeinside a helical tension spring 32 is secured ltothe cross pins 33 and 34, mounted inthe otherlead wire 26 is connected to the switch mounting 27- by a screw 28 which also serves-iY as a binding post. 1

The switch mounting 27 has a; circularly enlarged portion 28. throughv the center of which a pivot pin 29 is passed and to which the switch lever 14 is pivoted. An 'inde-fY pendently movable switcharm 30 is also l'piv- `oted to the pin 29, this switch arm being'p'referablyforked to receive the lever V14fbetween them as clearly shown in vFigure 3. At each lever 14 andswitch arm 30 Vrespectively and extending ,laterally to f points where -`the springs mayswing from side to side, when lever 14 `is being manipulated, without contacting withlthe mounting 27...k TheA body members 10l and 11 are ifnteriorlyV recessed to provide a cavity of sufficient Vsize for the switch and mounting27 andjsprings32.

Theksocket terminal 21 Vis connected'by the'sorew 22 witha stationary switch ter- 4 minal 35 which preferably carries a contact Like parts are identified by the same refr portion 361(Fig. 4) and an oil' set contact portion 37 both of which may be simultaneously engaged by a contact roller 38, carried by the switch arm 30. The roller is preferably `iournalled upon thejplivot pin"34. y

From fthe foregoing description the oper- .fation of the switch will be obvious." Movement of the `Operating piece or lever 414 toward the vright `from its position as shown by full lines'in Figure 2 to the dotted line poy .sition will carry. the springs 32. across thelcentral planeindicated by the line 3-3 Fig-V ure 2 to a point where'the re'a'ctionf'of the springs 32 will retract the switch arm 30 to the dotted line position with the roller in contact with the recess body walls of insulating material. Movement of the lever 141 in the opposite direction will again carry the springs across the central plane whereupon they will swing the contact roller 38 to the stationary terminal members 36 and 37. If the socket members 2O and 21 are Ythen in engagement vwith the terminal posts of a heating unit, the circuit will be closed-through the heating unit from terminal socket 2O to terminal socket 21 and through the switch.

The exposed end of the switch lever llibeing covered by a sheath of insulating material 38, it is obvious that the electrical current cannot follow lever 14 to the exterior and all Aofitheassociated parts are completelyinsulatedfbjythebody members 10, 14 and 15 from i the vsocketterrninalf20 and its associated elec- `trical connections. The switch proper, including the springs 32, Aare located 'at `the outeriend of the body and the insulating mafterial composingthe bodymembers 10 and11 ,are also non-heat conductive. i

j V Material heat conduction'can take place only through the limited areas -or `paths for such conduction afforded by the stationary vcontact members 36 and V37 whereby only-a slight vnumber of heat units may reach the roller 38 and associated parts. It will,therel:Eore,beobvious that the movable partsof the switchmechanismwill have substantially the same durability that they would have'if they were not employed for connectingup thecircuit of an electric heater or otherwise exposed to lthe high temperatures of such heaters. l A The location of the'cord at one'side lof the central axis of the switch plug and in-an y obliquepositiom (preferablyat approximateily a angle to said axis) vtends to keep the .cord at one side-of the field oli-operations of. a sad iron or other tool to which the plug 45 maybe connected, since very 'few movements when moving :from `closed to open position. When .the fplug is in the `oblique position inV ofigthe tool lwill be in line withftheportion of thecord which is connected to the plug.

It will be .observed that the switchsocket 40 'extends :across the central transverse plane of the body indicated bythe line 3--3 in Figure 2 and that the switch and also the switch .operating :lever liswing across this plane which it is shown in Figure 5 the lever will vbezplainly visible, whereby it can be determined by inspection whether :the switch is in -the open or closed position.v By allo-wing the plugcavities 42 and t3-to ventilato along the socket `terminals 2O and 21 to a cord receiving recess or socket at `the side of .thel

plug the heat is carriedjaway without reaching theswitch cavity 42. .Cavi-ty 4,3 com` .municates vwith the upper Yend .of l,cavity .412A c5 through the transverse groove 44,

lever being eacharrangedto swing :to Aopen While it is not novel to employ independently movable switch actuating levers and switch arms which are connected by tension springs moving across a pivot line common to the lever and switch arm, yet such switch operating mechanism has not Y heretofore been thought adaptable for switch plugs asmechanismabove described. y v

1. A switch plug orelectric heaters-coin-` prisiiig the combinationof an Ainsulating body havin-gaswitch recess atone end and a plugvportion at the other end, each located .across the axial centerline of the plug, a switch in theswitch recess having `an oper-- l.ating lever extend-ing `through anendslot in the .body said ,plug portion being-provided with vented electrical terminals and the .body having llateral electrical connections Ycontrolled. by the. switch, said switch.;

and its operating lever .being each arranged to swing to kopen and closed positions across an axial central .plane transverseto' that ot lever and switch movement, and a stationary contact member `for the switch at tthe innen endporti'on ofthe switch recess in electrical connection with oneotl the socket terminals.

2. A switch plug for electricheaterscoinprising the combination of an insulatingV bodyT having a switch'recess 4atvone' end 4and` a plug portionatthe other end, each -located across the axial center line yof the plug, aV

switch in the switch recess 'having anoperating lever extending through van end slot 1n the body, said switch and itsoperating lever-l being each arranged to swing to open and closed .positions `across an axial central planeV v t-ransverse to ,thatolj' lever and switch movement terminal fsocket members .in `the plug,

and a stationary contact terminal for .thc-gj l switchl at the inner .end portion of the switch recess electrically connected with one o'l' .the

socket,k terminals, V:said body'V having an .oblique ,current `supply connection 4in periio manent electrical connection with the switch-izo and 4the other socket terminal.

y '3. A switch plug for electric hea-ters 'coin- .prising :the combination. of an insulating `body having a switch recess. at on-e end and :a plug portion yat the other end, .each located-1 :across the axial centerline of the plug, a switch inthe switch recess having V`an operating lever extending through an .end slot in the body, said switch and its operating ing through an opening in one side of the body and connected with the other plug socket terminal and with the switch respectively, said body being in two parts separable in a plane substantially co-incident with that of the lever and switch movement and having the plug portion connected with its opposite end by a metal sheath in coupling relation to the body members said metal sheath being secured to the respective ends of the body at points laterally 'offset from the cavities therein.

4. A switch plug having a body provided with a switch cavity at one end and a plug portion at the other end, said plug portion containing socket terminals, and 'a body having a laterally extending cord receiving socket serving as a Ventilating passage in communication with space about said socket terminals whereby said switch cavity may be isolated and heat insulated by the body.

5. A switch plug having a body provided with a switch cavity at one end andra plug portion at the other end, said plug portion containing socket terminals, and a body having a laterally extending cord receiving socket serving as a Ventilating passage in communication with space about said socket terminals whereby said switch cavity may be isolated and heat insulated by the body, said switch cavity having a contact terminal at its inner end connected with one of the socket terminals and also having 'apivoted switch arm adapted for contact with said terminal, and an operating lever fulcrumed at the axis of the switch arm and intermedi'ately connected with the switch arm by tension springs adapted to swing the switch arm across a central plane which inminals having a forked stationary contact member at the inner end of said socket, a switch mechanism in said socket yprovided with a roller adapted to be moved into and out of engagement with said forked contact member, and means vfor Ventilating the space in which the socket terminals are located, laterally vof the switch receiving socket.

CHARLES c. MAURnR. NORMAN D. VEA.

cludes the pivot axis when the lever is swung across such plane.

6. In a switch plug mechanism for electric heaters, the combination with a body portion having an isolated switch receiving socket, socket terminals substantially heat insulated from saidsocket, one of said terminals having a forked stationary contact member at the inner end of said socket, and 'a switch mechanism in said socket provided with a roller adapted to be moved into and out of engagement with said forked contact member.

7 In a switch plug mechanism Jfor electric heaters, the lcombination with ay bodyV portion having an isolated switch receiving socket, socket terminals substantially heat insulated from said socket, one of said ter- 

